Certain types of footwear are known and commercially available that reproduce the natural shape of the foot, in order to ensure better articular mobility especially of the toes and to give more comfort during the action of walking, giving the user the sensation of walking on bare feet while ensuring the necessary protection.
Such a type of footwear is described in the international patent application WO2007/038487 of the same applicant. This patent application describes a shoe in which the front part defines multiple portions independent of each other made of flexible material to accommodate the toes; such portions involve both the upper and the sole of the shoe.
These shoes have a non-slip sole which, although being made with a thin enough thickness and elastic material like rubber and similar, may not allow for a desired yielding during the execution of foot movements. The shoe, therefore, is extremely soft and yielding in the upper part, namely in the portion that covers the dorsum of the foot, while being stiffer at the sole, as the sole itself must ensure, however, a cushioning and protective effect of the plantar surface of the foot, that is, the surface of the foot that supports the weight of the user.
Furthermore, the sole of the above-mentioned known footwear does not guarantee, in particularly hard use conditions, as in the execution of extreme sports or similar, a sufficient non-slip grip on more difficult surfaces, such as those that are very slippery or inclined.